Simulation Study of the Effect of Fractures on Convective Heating Efficiency in Oil Shale

Abstract

Oil shale, as an unconventional energy source, has attracted much attention in countries worldwide. The traditional way of extracting oil shale from the open pit is not only costly but also polluting to the environment. Sufficient understanding of the relationship between subsurface fractures and temperature fields is important for the extraction of oil shale and is of great significance for the actual in-situ extraction of oil shale. The study of fracture initiation and expansion in oil shale formations is based on the effect of fractures on convective heating efficiency in oil shale in situ conversion technology. In view of the objective situation that hydraulic fracturing can enhance the rate of the permeability and heating efficiency of oil shale formations, and hence the oil yield, the effect of single fractures with different fracture heights (2 mm, 4 mm, 8 mm) on the temperature field of oil shale; and the effect of multiple fractures (two, three and four fractures) on the temperature field of oil shale are investigated under convective heating methods.